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Finding the Fourth Proportional to 79.24, 109.86 and 78.10

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Solution

The fourth proportional to 79.24, 109.86 and 78.10 is: 108.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.24 : 109.86 = 78.10 : x
  2. Step 2: Convert to fraction form
    79.24/109.86 = 78.10/x
  3. Step 3: Cross multiply
    79.24x = 109.86 × 78.10
  4. Step 4: Simplify right side
    79.24x = 8,580.07
  5. Step 5: Solve for x
    x = 8,580.07/79.24
  6. Step 6: Final answer
    x = 108.28

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.